Vitamin K dependent protection of renal function in multi-ethnic population studies

Background: Following activation by vitamin K (VK), matrix Gla protein (MGP) inhibits arterial calcification, but its role in preserving renal function remains unknown. Methods: In 1166white Flemish (mean age, 38.2 years) and 714 South Africans (49.2% black; 40.6 years), we correlated estimated glomerular filtration (eGFR [CKD-EPI formula]) and stage of chronic kidney disease (CKD [KDOQI stages 2â 3]) with inactive desphospho-uncarboxylated MGP (dp-ucMGP), using multivariable linear and logistic regression. Results: Among Flemish and white and black Africans, between-group differences in eGFR (90, 100 and 122 mL/min/1.73 m2), dp-ucMGP (3.7, 6.5 and 3.2 μg/L), and CKD prevalence (53.5, 28.7 and 10.5%) were significant, but associations of eGFR with dp-ucMGP did not differ among ethnicities (P â ¥ 0.075). For a doubling of dp-ucMGP, eGFR decreased by 1.5 (P = 0.023), 1.0 (P = 0.56), 2.8 (P = 0.0012) and 2.1 (P b 0.0001) mL/min/1.73 m2 in Flemish, white Africans, black Africans and all participants combined; the odds ratios for moving up one CKD stage were 1.17 (P = 0.033), 1.03 (P = 0.87), 1.29 (P = 0.12) and 1.17 (P = 0.011), respectively. Interpretation: In the general population, eGFR decreases and CKD risk increaseswith higher dp-ucMGP, a marker of VK deficiency. These findings highlight the possibility that VK supplementation might promote renal health. © 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY licensepublisher: Elsevier articletitle: Vitamin K Dependent Protection of Renal Function in Multi-ethnic Population Studies journaltitle: EBioMedicine articlelink: http://dx.doi.org/10.1016/j.ebiom.2016.01.011 content_type: article copyright: Copyright © 2016 The Authors. Published by Elsevier B.V.status: publishe